Both merchants and mailing list services maintain customer databases, which they use to print addresses for mailing pieces. As these lists become large, the impact of postal rates can be enormous. In general bulk mailing postal rates are dependent upon the amount of presorting that is done prior to delivery of the mail to the post office. Postal presorting is a process where a mailing list of names and addresses is arranged in such a way as to reduce the amount of work needed to be done by the post office to handle that mail.
Presort discounts are related to the number of mail pieces addressed with the same, or similar, zip code classifications. The amount of postage discount available varies with the level of zip code classification, the greatest discount being for carrier route (pieces delivered by the same mail carrier in a single zip code, then for five digit zips, then for three digit zips (first three digits of a zip code are the same), then for Area Distribution Centers (abbreviated “ADC” and referring to offices serving multiple three digit zips), and finally for mixed ADCs a catch all for mail pieces that don't have sufficient quantities to qualify at one of the higher levels. These zip code classifications are known as presort levels. In order to achieve postage discounts for presorting, the mail is presented in containers such as trays, which must be arranged in such a way so as to contain appropriate quantities of mail for the various presort levels.
It is known to use computer systems to create a mailing based on presort discounts, by sorting each physical mail pieces. U.S. Pat. No. 5,475,603 to Korowotny (December 1995) teaches a system that scans the zip codes on individual mail pieces (by optical character recognition) to determine the quantities of mail that qualify for a presort level discount. One significant drawback is that Korowotny's system is only practical with a sequential, or at least almost sequential, mailing list. Even there, Korowotny's system works well for relatively short list. When a mailing is large, sorting individual pieces becomes too time intensive.
A better strategy is to sort a mailing list rather than the printed items. U.S. Pat. No. 5,377,120 to Humes et al. (December 1994) teaches a system that aggregates the mailing lists of a plurality of merchants, and groups the addresses according to the lowest presort level rates. However, such a system typically takes several hours to sort a 10 million address list into presort levels, mostly because the computer must use a disk-based algorithm during the sortation.
Korowotny, Humes and all other extrinsic materials discussed herein are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
In view of the shortcomings of the prior art, there is still a need for systems, methods and apparatus that decrease the overall time required for a computer system to presort a mailing list into presort level discounts.